[PATCH 2/3] libata: Add firmware_default LPM policy
From: Matthew Garrett
Date: Sat Apr 18 2015 - 11:27:27 EST
System vendors may configure SATA link power management appropriately for
their systems in firmware, based on their knowledge of the hardware
installed. Add an additional LPM policy designed to inherit the
configuration provided by the firmware.
Signed-off-by: Matthew Garrett <mjg59@xxxxxxxxxx>
---
.../scsi/link_power_management_policy.txt | 5 +-
drivers/ata/libahci.c | 62 +++++++++++++++-------
drivers/ata/libata-core.c | 7 ++-
drivers/ata/libata-eh.c | 15 +++---
drivers/ata/libata-scsi.c | 1 +
include/linux/libata.h | 1 +
6 files changed, 63 insertions(+), 28 deletions(-)
diff --git a/Documentation/scsi/link_power_management_policy.txt b/Documentation/scsi/link_power_management_policy.txt
index d18993d..0285601 100644
--- a/Documentation/scsi/link_power_management_policy.txt
+++ b/Documentation/scsi/link_power_management_policy.txt
@@ -1,8 +1,11 @@
This parameter allows the user to set the link (interface) power management.
-There are 3 possible options:
+There are 4 possible options:
Value Effect
----------------------------------------------------------------------------
+firmware_defaults Inherit configuration from the state programmed by
+ the firmware during system init.
+
min_power Tell the controller to try to make the link use the
least possible power when possible. This may
sacrifice some performance due to increased latency
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index f0c7120..fabcff4 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -684,6 +684,7 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
{
struct ata_port *ap = link->ap;
struct ahci_host_priv *hpriv = ap->host->private_data;
+ struct ahci_port_priv *ppriv = ap->private_data;
struct ahci_port_priv *pp = ap->private_data;
void __iomem *port_mmio = ahci_port_base(ap);
@@ -701,9 +702,9 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
if (hpriv->cap & HOST_CAP_ALPM) {
u32 cmd = readl(port_mmio + PORT_CMD);
+ cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE);
if (policy == ATA_LPM_MAX_POWER || !(hints & ATA_LPM_HIPM)) {
- cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE);
cmd |= PORT_CMD_ICC_ACTIVE;
writel(cmd, port_mmio + PORT_CMD);
@@ -711,6 +712,13 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
/* wait 10ms to be sure we've come out of LPM state */
ata_msleep(ap, 10);
+ } else if (policy == ATA_LPM_FIRMWARE_DEFAULTS) {
+ if (ppriv->init_alpe)
+ cmd |= PORT_CMD_ALPE;
+ if (ppriv->init_asp)
+ cmd |= PORT_CMD_ASP;
+
+ writel(cmd, port_mmio + PORT_CMD);
} else {
cmd |= PORT_CMD_ALPE;
if (policy == ATA_LPM_MIN_POWER)
@@ -725,10 +733,17 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
if ((hpriv->cap2 & HOST_CAP2_SDS) &&
(hpriv->cap2 & HOST_CAP2_SADM) &&
(link->device->flags & ATA_DFLAG_DEVSLP)) {
- if (policy == ATA_LPM_MIN_POWER)
+ switch (policy) {
+ case ATA_LPM_MIN_POWER:
ahci_set_aggressive_devslp(ap, true);
- else
+ break;
+ case ATA_LPM_FIRMWARE_DEFAULTS:
+ ahci_set_aggressive_devslp(ap, ppriv->init_devslp);
+ break;
+ default:
ahci_set_aggressive_devslp(ap, false);
+ break;
+ }
}
if (policy == ATA_LPM_MAX_POWER) {
@@ -1995,6 +2010,7 @@ static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep)
{
struct ahci_host_priv *hpriv = ap->host->private_data;
+ struct ahci_port_priv *ppriv = ap->private_data;
void __iomem *port_mmio = ahci_port_base(ap);
struct ata_device *dev = ap->link.device;
u32 devslp, dm, dito, mdat, deto;
@@ -2030,26 +2046,32 @@ static void ahci_set_aggressive_devslp(struct ata_port *ap, bool sleep)
if (rc)
return;
- dm = (devslp & PORT_DEVSLP_DM_MASK) >> PORT_DEVSLP_DM_OFFSET;
- dito = devslp_idle_timeout / (dm + 1);
- if (dito > 0x3ff)
- dito = 0x3ff;
+ if (ppriv->init_devslp) {
+ dito = ppriv->init_dito;
+ deto = ppriv->init_deto;
+ mdat = ppriv->init_mdat;
+ } else {
+ dm = (devslp & PORT_DEVSLP_DM_MASK) >> PORT_DEVSLP_DM_OFFSET;
+ dito = devslp_idle_timeout / (dm + 1);
+ if (dito > 0x3ff)
+ dito = 0x3ff;
- /* Use the nominal value 10 ms if the read MDAT is zero,
- * the nominal value of DETO is 20 ms.
- */
- if (dev->devslp_timing[ATA_LOG_DEVSLP_VALID] &
- ATA_LOG_DEVSLP_VALID_MASK) {
- mdat = dev->devslp_timing[ATA_LOG_DEVSLP_MDAT] &
- ATA_LOG_DEVSLP_MDAT_MASK;
- if (!mdat)
+ /* Use the nominal value 10 ms if the read MDAT is zero,
+ * the nominal value of DETO is 20 ms.
+ */
+ if (dev->devslp_timing[ATA_LOG_DEVSLP_VALID] &
+ ATA_LOG_DEVSLP_VALID_MASK) {
+ mdat = dev->devslp_timing[ATA_LOG_DEVSLP_MDAT] &
+ ATA_LOG_DEVSLP_MDAT_MASK;
+ if (!mdat)
+ mdat = 10;
+ deto = dev->devslp_timing[ATA_LOG_DEVSLP_DETO];
+ if (!deto)
+ deto = 20;
+ } else {
mdat = 10;
- deto = dev->devslp_timing[ATA_LOG_DEVSLP_DETO];
- if (!deto)
deto = 20;
- } else {
- mdat = 10;
- deto = 20;
+ }
}
devslp |= ((dito << PORT_DEVSLP_DITO_OFFSET) |
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c037f33..0a78f01 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2024,7 +2024,7 @@ retry:
}
}
- if (id[79] & SATA_DIPM)
+ if (id[79] & (1 << SATA_DIPM))
dev->init_dipm = true;
*p_class = class;
@@ -3672,6 +3672,11 @@ int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
return rc;
switch (policy) {
+ case ATA_LPM_FIRMWARE_DEFAULTS:
+ /* use the values we read at probe */
+ scontrol &= ~(0x7 << 8);
+ scontrol |= (link->init_lpm << 8);
+ break;
case ATA_LPM_MAX_POWER:
/* disable all LPM transitions */
scontrol |= (0x7 << 8);
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 07f41be..c36fa56 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -3519,9 +3519,9 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
return 0;
/*
- * DIPM is enabled only for MIN_POWER as some devices
- * misbehave when the host NACKs transition to SLUMBER. Order
- * device and link configurations such that the host always
+ * DIPM is enabled only for MIN_POWER and FIRMWARE_DEFAULT as some
+ * devices misbehave when the host NACKs transition to SLUMBER.
+ * Order device and link configurations such that the host always
* allows DIPM requests.
*/
ata_for_each_dev(dev, link, ENABLED) {
@@ -3581,10 +3581,13 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
if (ap && ap->slave_link)
ap->slave_link->lpm_policy = policy;
- /* host config updated, enable DIPM if transitioning to MIN_POWER */
+ /* host config updated, enable DIPM if transitioning to MIN_POWER or
+ * FIRMWARE_DEFAULT when enabled by firmware
+ */
ata_for_each_dev(dev, link, ENABLED) {
- if (policy == ATA_LPM_MIN_POWER && !no_dipm &&
- ata_id_has_dipm(dev->id)) {
+ if ((policy == ATA_LPM_MIN_POWER && !no_dipm &&
+ ata_id_has_dipm(dev->id)) ||
+ (policy == ATA_LPM_FIRMWARE_DEFAULTS && dev->init_dipm)) {
err_mask = ata_dev_set_feature(dev,
SETFEATURES_SATA_ENABLE, SATA_DIPM);
if (err_mask && err_mask != AC_ERR_DEV) {
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 3131adc..f1ea052 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -107,6 +107,7 @@ static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
static const char *ata_lpm_policy_names[] = {
[ATA_LPM_UNKNOWN] = "max_performance",
[ATA_LPM_MAX_POWER] = "max_performance",
+ [ATA_LPM_FIRMWARE_DEFAULTS] = "firmware_defaults",
[ATA_LPM_MED_POWER] = "medium_power",
[ATA_LPM_MIN_POWER] = "min_power",
};
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 31c149b..57b465d 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -507,6 +507,7 @@ enum ata_completion_errors {
enum ata_lpm_policy {
ATA_LPM_UNKNOWN,
ATA_LPM_MAX_POWER,
+ ATA_LPM_FIRMWARE_DEFAULTS,
ATA_LPM_MED_POWER,
ATA_LPM_MIN_POWER,
};
--
2.3.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/